Kindred Healthcare, a provider of acute care hospital and inpatient rehabilitation services, says it has agreed to buy rival RehabCare Group for about $900 million in cash and stock.

The combined company will have about $6 billion in annual revenue and operate 118 long-term acute care hospitals, 226 nursing and rehabilitation centers and 121 inpatient rehabilitation hospitals.

Kindred Healthcare Inc. says it will pay about $35 per share for RehabCare Group Inc., a 37.4 percent premium over Monday's closing price. It will pay $26 in cash and 0.471 Kindred shares for each RehabCare share.

Kindred will also assume about $400 milion in RehabCare debt.

The companies expect the sale to close around June 30.

Kindred is based in Louisville, Ky., and RehabCare is based in St. Louis.